On Friday night, Jodrell Bank Observatory was turned into Jodrell Bank School of Astronomy & Astrophysics for the release of Harry Potter and the Deathly Hallows. Around 120 people turned up to enrol as students for the night. On arrival everyone was sorted into one of the four houses by a sorting hat which actually spoke. The four houses were all animal constellations visible from the northern hemisphere and everyone was given a house badge.

The four house logos for the Jodrell Bank Harry Potter book launch night 20/7/2007 CREDIT: Stuart and constellation images from the excellent Stellarium.

Once sorted, house prefects (PhD students and astronomy postdocs) took the four houses to their different activities which included a 3D trip to Mars, a planetarium show, an astronomy lecture and a chance to make wands and wizard hats. The event was billed as a star party and there would have been a chance to look through telescopes too if the rain had given us a chance. At least we weren't flooded like many other places in the north of England.

I wanted to make sure that the event had the right atmosphere so there were some other special touches. The driveway was lined with flags in the house colours, floating candles (unlit for health and safety reasons) were in the great hall, there were animated paintings with the subjects walking between them, and all the staff were dressed in robes (which took a few of us quite a while to sew together). We also had a few broomsticks (made with twigs and branches collected from the arboretum) for good measure.

Around midnight we had a webcast from J.K. Rowling via the Bloomsbury website although it started late and I ended up effectively being the warm up guy for JK! At 00:01 BST the book went on sale and those that had ordered them from us were able to pick them up.

Throughout the evening we also had a guy from the Daily Prophet - alternatively known as Granada Reports - who did some filming for Saturday's evening news report on ITV1 (available until next Saturday online). It was the first time I have ever been interviewed for TV and I also had to do a set piece to the camera. I am happy to say that I didn't fluff my lines, although the reporter needed quite a few takes partly because he kept saying astrology rather than astronomy! I really like the fact that an astronomical observatory got the Harry Potter slot rather than the supermarkets or big book sellers. We were certainly more exciting.

As far as I can tell (I haven't read the feedback forms yet) I think everyone had a good night. I know I did. If you have any Harry Potter star party or sidewalk astronomy stories, let me know in the comments below.